Dyestuffs containing chromium



Patented Apr. 1, 1930 UNITED STATE PATENT orrlca OF MANNHEIMI, GERMANY, ASSIGNOR TO GENERAL ANILINE WOI BKS, INCL, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE DYESTUFFS CONTAINING GHROMIUM in Drawing. Application med April 13,1928, Serial No. 269,875, and in Germany Hay-14, 1927.

This invention relates to the production of new dyestuffs containing chromium.

It has already been suggested to produce chromiferous pyrazolone dyestuffs'by treating o-hydroxyazodyestufis of the pyrazolone series, containing an SO NH group in the aryl nucleus of the arylpyrazolone body with agents supplying chromium.

I havenow found that chromiferous dyestuffs with similar properties are obtained if the dyestuffs obtainable by coupling diazotized o-amino-naphthols, or their derivatives with sulfo-aryl-methyl-pyrazolones containing sulfonic groups instead of the amides thereof are treaded with agents supplying chromium. It results that the valuable properties of the dyestuffs mentioned above do not depend as was hitherto supposed, on the presence of a ,sulfamidq group. The process according to this invention constitutes an important improvement, inasmuch as the sulfamino-arylmethylpyrazolones are difiicult and troublesome to produce. The dyestuffs obtained according to this invention are distinguished by being fast to milling and produce even dyeings. The following examples will further illustrate the nature of my invention which howso ever is not limited thereto. The partsare by weight. F

Example 1 500 parts of the azo dyestulfs obtainable by coupling the diazo compound of l-amino- 2-naphthol-4-sulfonic acid with '1- (3'-sulf0.)-

phenyl-B-methyl-5-pyrazolone are heated at 120 centigrade for 3 hours in an autoclave .with 1400 parts of water, 500 parts'of 27.5 per cent of chromic acid and 250 parts of 85"per 40 centformic acid. The resulting dyestufi' solution is then salted 'outor eva orated to dryness. The product gives excel ently even pink dyeings on wool, which are very fast to washing and milling.

- Example? I 250 parts of the dyestufi' obtainable by coupling the diazo-compound of nitrated 1-amino-2-naphthol-4-sulfonie acid with 1+ (4'-su1fo) phenyl-3-methyl-5-pyrazo1one are heated to centigrade for 3 hours in a closed vessel with 650 parts of a chromium formate' solution containing 68 parts of chromium hydroxide, the solution bemg then salted out or evaporated. The resulting dyestuif gives yellowish-red even dyeings on wool, very fast to washing and milling.

The chromiferous dyestufis may also be prepared in any other convenient manner by treating the initial materials with any other suitable chromium compound, also for 'example by longer boiling under ordinary pressure.

Ewample 3 250 parts of the azo dyestufi obtainable by coupling the diazo com ound. of nitrated 1-amino-2-naphthol-4-sul onic acid with. 1- (3-sulfo) -phenyl-3- methyl-5- pyrazolone are heated for 3 hours in an autoclave with 650 parts of a chromium formate solution-containing 68 parts of chromium hydroxide to 120 centigrade. The dyestufi thus obtained is salted out and dried. It dyes wool in well equalized yellowish-red shades, which are very fast to washing, milling and light.

WhatIclaimis:

1. As new articles of manufacture,chromiferous dyestuffs fast to washing, milling and light, which are the chromium compounds of the azo-dyestuffs from diazotized o-amino-naphthols and sulfo-phenyl-methylpyrazolone 9 2. As new articles of manufacture, chromiferous dyestuffs fast' to washing, milling and light, which arethe chromium compounds of the azo-dyestufis from diaz otized' 1-amino 2-naphthol4-sulfonie acid and sulfo-phenyLmethyl-pyrazolones.,

1 .3. As a new article of manufacture 'the chromiferous dyestufis fast to -was 'n'g, milling and light, which is the chromium com ound of the azo-dyestuffs from diazotlzed 1-ami'no-2-naphthol-4-su1fonic acid with 1-(3'-sulfo) -phenyl-3- methyl- 5-pyraz-. clone. 1

In testimony whereof I have hereunto set my'hand.

KAMMEREB. 

